Don't send the subbuffer padding for streaming

[lttng-tools.git] / src / common / ust-consumer / ust-consumer.c

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index 2b8098835857106a811f03761fcafe7489f1ce1f..e7d6dd4e780084879759055fe839e018f6d02048 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -228,14 +228,29 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                        goto end_nosignal;
                }
 
-               if (ctx->on_recv_stream != NULL) {
-                       ret = ctx->on_recv_stream(new_stream);
-                       if (ret == 0) {
-                               consumer_add_stream(new_stream);
-                       } else if (ret < 0) {
-                               goto end_nosignal;
+               /* Send stream to the metadata thread */
+               if (new_stream->metadata_flag) {
+                       if (ctx->on_recv_stream) {
+                               ret = ctx->on_recv_stream(new_stream);
+                               if (ret < 0) {
+                                       goto end_nosignal;
+                               }
+                       }
+
+                       do {
+                               ret = write(ctx->consumer_metadata_pipe[1], new_stream,
+                                               sizeof(struct lttng_consumer_stream));
+                       } while (ret < 0 && errno == EINTR);
+                       if (ret < 0) {
+                               PERROR("write metadata pipe");
                        }
                } else {
+                       if (ctx->on_recv_stream) {
+                               ret = ctx->on_recv_stream(new_stream);
+                               if (ret < 0) {
+                                       goto end_nosignal;
+                               }
+                       }
                        consumer_add_stream(new_stream);
                }
 
@@ -384,7 +399,7 @@ void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream)
 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
                struct lttng_consumer_local_data *ctx)
 {
-       unsigned long len;
+       unsigned long len, subbuf_size, padding;
        int err;
        long ret = 0;
        struct lttng_ust_shm_handle *handle;
@@ -411,7 +426,7 @@ int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
        /* Get the next subbuffer */
        err = ustctl_get_next_subbuf(handle, buf);
        if (err != 0) {
-               ret = -ret;     /* ustctl_get_next_subbuf returns negative, caller expect positive. */
+               ret = err;      /* ustctl_get_next_subbuf returns negative, caller expect positive. */
                /*
                 * This is a debug message even for single-threaded consumer,
                 * because poll() have more relaxed criterions than get subbuf,
@@ -423,12 +438,21 @@ int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
                goto end;
        }
        assert(stream->output == LTTNG_EVENT_MMAP);
-       /* read the used subbuffer size */
+       /* Get the full padded subbuffer size */
        err = ustctl_get_padded_subbuf_size(handle, buf, &len);
        assert(err == 0);
+
+       /* Get subbuffer data size (without padding) */
+       err = ustctl_get_subbuf_size(handle, buf, &subbuf_size);
+       assert(err == 0);
+
+       /* Make sure we don't get a subbuffer size bigger than the padded */
+       assert(len >= subbuf_size);
+
+       padding = len - subbuf_size;
        /* write the subbuffer to the tracefile */
-       ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len);
-       if (ret != len) {
+       ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size, padding);
+       if (ret != subbuf_size) {
                /*
                 * display the error but continue processing to try
                 * to release the subbuffer